Hi allI've a cream 100 % polyester dress that I wish to colour. I've looked at the synthetic dyes and the colours are a tad bright for this occasion. Does anyone know how to tone the greens down? To maybe a more olive or khaki green? Or should I make a paler green mix? I really don't want a minty colour, ideally a more earthy colour! Any ideas?

The regular green actually gives you a very mossy green if you dye it for the full hour. If you want to tone down the Kelly green or the regular green to a more earthy look, you want to "tone" it. Toning is adding less than 10% dye usually in complementary color to knock the brightness down or dull the color. The benefit is that it does not looks os chockingly bright, but it also gives a depth to the color that is very nice.

I would suggest toning with the complementary color red at about 7%. That can be difficult if you are trying to measure the weight of the dye. The easier way is to dissolve the red in say a quart of hot water and use 3 oz(just under half a cup) of that solution in your green. Test with an old white sock(socks usually have some poly content) to make sure it is the right color. If it isn't earthy enough for you add more red in 1/4 to 1/2 increments. It will change faster than you think, so small increments are a good idea.

The amount of fabric is the more important thing. You want to dye at about 2-4%. Below that it will be very pale and above that the fabric can't hold that much and it will rub off. So it is 1/2 an ounce of dye and that pack will dye 1-3lbs of fabric. If you want to dye less than that, 1/2 a lb for instance, use half the package. It come sin a dissolvable corn starch package. The best way to get 1/2 is to dissolve the whole thing in a pint of hot water and use 1/2 of it.